Scroll to see break-even price per barrel for oil in 2015 for select oil producers, and click on a country's name for more details. modest oil-price recovery and currency devaluations have lowered breakeven prices for countries like Russia and Nigeria, but some petrostates still need oil prices above $100 a barrel to balance their budgets.
There are dozens of types of gemstones â including diamonds, colored gemstones, and pearls â each with a unique set of physical and optical properties. GIRDLE â The narrow band around the perimeter of a polished or faceted diamond or colored gemstone.
Gemstone Description Terminology in General. In the past, the term trilliant-cut could only be used to describe brilliant-cut, triangular gemstones (hence the name tri-lliant), but nowadays, the term can be used to describe any triangular gemstone including step cuts, cabochons and even plain cuts. Cutting styles and shapes have evolved greatly.